I prefer the tubs, mostly for cleanliness. I can pull a tub, dump the bedding, and wash/sanitize it in a couple minutes. and they are super light and easy to handle. Drop one and it does not shatter.
Once I got up to a dozen 20 gal long tanks and lids years ago, it took for ever to properly clean/sanitize the heavy tanks, one slip and ya had a cracked tank. Also, a rack system lets you get the most out of the space in a herp room. This Is all just my opinion, it is what works for me. I like to completely wash and sanitize every tub every 2 weeks, as my herp room is in my house on the main floor. I could never keep the collection I have if I had everything in tanks.
BUT, buy or build a rack for the purpose of keeping snakes. those little racks that walmart sells are not going to prevent an escape. take a close look at one and you will see all the gaps. Sorry I misread your post before I wrote all the above.