Hydraulic roller is low maintenance after setup also. A little higher performance potential and not as sensitive to oil type. Its just more expensive and may require more setup as the B/RB wasn't made for it originally.

PS: One drawback of the hydraulic roller is match with oil pump gear. B/RB roller cam cores are hard steel vs iron used for flat tappet. The steel oil pump drive gear machined into the cam does not work well with the stock style steel oil pump shaft drive gear. They do not make a good "wear pair" and bacically destroy each other. The fix is to run a bronze OP drive shaft gear. The drawback is wear of the bronze gear. Depending on lots of variables, it may last a few thousand miles or 10k+. The gear becomes a wear item. If there were iron core roller cores for street cams this problem would go away... I just don't think there are any.

This makes the flat tappet, with correct oil, a better choice in my book if you want to run some miles. Personally, I favor (and run) the mechanical flat tappet as performance potential is similar to a street hydraulic roller. I don't mind checking valve lash once in a while.

You are looking for lower maintenance so that favors the hydraulic flat tappet.