The B7 would by far be the best bang for the buck but I understand why you wouldn't want to go that way.
The XE9005 is very good, any lower than that (in EU at least...) and the HDR experience would be seriously compromised.
Keep in mind that next year may bring HDMI 2.1 which by itself might be a good reason to wait if you intend to keep your TV for at least 5-6 years (alternatively you coud snag a XF9005 on the cheap for example)
And considering that you wouldn't use 4k content for a while anyway I'd wait if I were you
I've checked what HDMI 2.1 will do and it has some decent benefits, although i wouldn't be using most of them. But damn, buying tech is such a pain, always the next hot thing around the corner. XD
I'm really itching to get the 55XE9005, but that lack of Dolby Vision support is getting to me a bit now. At first i thought that i don't really need DV, but having read about the different approach to HDR content via dynamic metadata compared to regular HDR made me waver again. That does sound much better, but the funny thing is, i don't even know if i'm going to have a device to play DV from, as i intend to use a PS5 for UHDs, whenever it comes out. Is it likely that PS5 would even support DV, or do you think Sony would rather skip the licensing fees and go for the opensource HDR10+?
XF9005 will get cheaper by next year, but i doubt the 55" model will go as extraordinarily low as this, even the 49XE9005 cost a bit more than that when they cleared out their stock this spring. If this one had gone out of stock during that time as well, there'd obviously not be this great sale on it now. Who knows if the 55XF900 stock will stick around long enough next year to get this cheap.
Another thing making my decision harder is that while the XF900 will be more future proof, it did slightly worse in some key categories for me (black levels without local dimming, input lag, black levels viewing angle) than the XE900, according to their respective Rtings reviews, so it's not even like it's a definite improvement over its predecessor. On the other hand, the XE900 seems to have some minor image retention issues. Man, why can't a TV set just be good, without any issues that you have to look past. :I
Go 55" if you can. The screen size jump to 55 is the single biggest improvement you will see since all content is not 4K.
It does sound like OLED solves all of your problems, so if you're okay with the panel lottery and some image retention now and then, it's not a bad idea. But if you want to go full trouble free, then LED is the only game in town. LG makes IPS displays where angle is not a problem, but I can see they're not your favorite company right now.
I don't think DV is a dealbreaker, but if you're big on UHD Blu Ray, maybe down the line? But I don't think of these sales as now or never. After World Cup will be Back to School, or Black Friday, or Pre Christmas, or Boxing Day - every country has a variety of them throughout the year.
I can't speak to the price because I can't really comprehend the currency. For example here in SG, TVs are just...arbitrarily a lot more expensive. The XF900 is $1000 cheaper in Canada and yet we have roughly equal currencies, which means there are retail controls that really change the market. Certainly something like the QF7 would be interesting, or the LG SK9000 in a big bright room, or the B7 if you are okay with trying OLED, but it REALLY depends on your particular market.
Price parity on the B7 to the XF is pretty impressive. I would have bought that on the spot here, but my family living room is far smaller than yours. Honestly speaking, if you're set on something now, the B7 is going to give you the best value by far. If you buy the XE90 and then go back to the store, the B7 is still going to seem like an improvement, and that's saying something. But I will say if you're not at 55" yet any set at that level will seem like an improvement.
The prices i listed are in Euros (1 EUR = 1,1667 USD), so the 55XE9005 would be 1365 USD, maybe even less, depending on how big of a coupon i would draw on checkout (between 10% - 50%).
Honestly, when i started looking at current TVs earlier this year i hadn't even considered anything above 49-50", because i thought i wouldn't be able to afford a decent set like Sony's 900 series at bigger sizes, so this price drop was quite the surprise. But now i think i do want a 55", so i'll either have to get this one, wait for them to possibly clear their XF stock in a similar sale this time next year, or save up more money and get the XF sooner. Speaking of which, they don't even have the 55XF900 in stock yet, but the 55XF800 set costs over 1500 EUR (1750 USD), so the 900 will probably be like 1800 EUR (2100 USD). :O
You are right of course that there will be more deals throughout the year, but they're not quite as numerous as in some places. For example, Back to School deals on TVs aren't really a thing here afaik, and Black Friday, while gaining popularity in recent years, doesn't comparable in terms of crazy prices either.
And yeah, i'd totally go for that OLED, if i wasn't so paranoid about possible burn in. I also don't trust my lack with panel lottery. The SK9000 wouldn't be up my alley, because i mostly watch during the evening/night,and the room isn't extremely bright even in daytime.
Anyway, thank you both for chiming in. As you can see from my ramblings, i'm still mulling it over, hoping that the stock will last long enough for me to make a decision. XD