I mostly throw 3-1/2" but 4" is definately not too big for a decent sized smallie.

4" tubes are my number one go to bait for smallmouth.  I have honestly caught several dozen fish in the 6-8" range on a 4" bait.  I am not sure if they are EATING it or picking it up to kill it, practicing for "later life" or if they're just curious.

There are times, however, where the 2.5" teaser really does excel.  In ultraclear water, or in COLD water (winter) I have found that the smaller profile bait gets ME more bites.

Buy 'em both!

Definitely not but I have had better luck with Teaser Tubes.

I like the 4".  Helps weed out the smaller fish.

I had been using BPS tender tubes and teaser tubes without any luck at all. The only tube that have really worked for are the Magnum tubes. Thats all I carry now for tubes.

I'll go small in the spring and larger in the fall 4" even 5" if the bite is hot.