I used t8 in my garage 3 or 4 years ago.
I bought the 2 lamp fixtures,with wrap around lenses, new, about 2 years prior for $15 per fixture.
I was planning on buying LED bulbs and just using the fixtures , stripping the ballasts and giving them to my electrician friend
I got a good deal on a case of bulbs about a year later. I think $3 a bulb.
if I run out of bulbs, burn out ballasts I will change to led. I have 4 spare fixtures tho, so in my life time, I wouldn't bet any money on changing , unless I start to spend a lot more time out there