Tough choice.. I own a few RIAs, no Tisas.. only 'cause of "timing" I really don't need ( or even want) another 1911
Don't shoot those I have enough as it is. here's my thoughts on the subject of RIA vs Tisas:
The RIAs were the 1st cnc-machined, made in the Philippines 1911's to come on the market..so tried one & it was good enough that I bought my 1st Officer sized 1911, ( which was also a RIA ) Both purchases were years before I heard of Tisas. The Tisas supposedly has a forged frame, which is better than cast, but in almost 50 yrs shooting 1911's , can't say I ever had an issue with any cast frame. As they are entry level priced, I'd probably try a Tisas...with the same attitude I had toward my first RIA purchase..if I don't like it, sell it. You won't lose much if you don't like it & want /need to sell it.
Truth is, you may get a gem or a lemon with either purchase.. & I'd say the odds are about the same with either brand.. My experience would be you'll probably be happy with whichever one you chose.