1080 ti there better then AMD and i was one who thought AMD was the best, till i bought two 1060 3 and 6gb and 2 1070 one is the normal 1070 and one is a ti an one 1080 so far there great and much better then AMD but some will debate that but I'm talking from experiencing it .I wish I had held out for NV cards when i bought 8 AMD cards and bought 4 to 5 NV cards an got more hash over all using less power with 3 to 4 nv cards then what 4 AMD cards do . Like i said some will debate that but they do and are better then AMD, i was a hard core AMD user.
I haven't bought a Vega yet,that's next on my list, just to see what it does ..
if you buy ASIC you can resell it but no were close what you paid for it in a year but more then likely it will have reached ROI by then or little longer if that's your end game when mining . so it's still worth it but then other issues may come up one being they are very loud now and unless you have a sound proofed mining room in your house or a building out back some place your best bet is GPU mining unless you can live with the noise, if you plan do it in your home, an 5k or more worth of GPU gear will fit about right in any home GPU mining . an do pretty good. I still plan to buy one A4 + full miner next year and use it in my home but also have a sound proofed room i use a A4 not Plus in now no one hears.
you can per order a L3 + from bit main off there site for 1651 USD or 0.12035730 BTC; 1.21528122 BCH; 11.84276594 LTC but won't get it till March ....right now.I wouldn't order anything that far into next year because a company in Japan might start selling there new 22 th miner with 7 nm chips about then or a little later and you can bet a better LTC miners won't be to far behind.. so you will be getting F*** unless you can get it now then buy it now but not for then.
http://Https://shop.bitmain.com/productDetail.htm?pid=0002017120420234742243Sqqip70697