I've never had a plain, so I can't compare grips with those models, but I recently picked up a StarTac 'Zaan and am just in love with both the look of it as well the feel in hand. I only got started on CRKs last summer but now also have a small coco Seb, large bocote 21, KA CF large 21, and snakewood Mnandi. I've got quite a few other knives, but none with plain metal handles, so I don't see myself picking up a plain Jane. After the StarTac, I could go for a large StarBenza--maybe a 25, as I don't have anything in that model. I'm also wondering about the Insingo blade on the 21s. Any comments on those, as I'm having a hard time figuring out the usefulness of that almost straight cutting edge?
To answer the OPs question, though, I find both my inlaid and CF CRKs very comfortable in hand and the StarTac every bit the same and really solid to hang onto. Really like the look of it, too.
BTW, wtlj and Ccc are spot on about buying from the exchange--I've picked up all my CRKs and plenty of blades at BF and you can't beat the prices and honesty of the forum members here. Whether buying a safe queen or a user, you'll eventually find what you want for a decent price and have a good experience to boot. Gotta say, you can't go wrong with either the quality of the merchandise or individuals here at BF. Good to be a part of this community...