Hi Scott.... - welcome to the forum!
By the 'stock keyboard on the iPad', do you mean the on-screen KB or the physical one offered by Apple - just not sure?
Also, you might want to tell us your particular needs (not sure why I'd want one w/ the letter-number option described?) - BUT, I've had the Apple BT KB for two years, and like Kevin, I don't use it often, however, when needed, it is indispensable: 1) On the road, the iPad is our web browser & email handler, for the latter in answering messages quickly, the BT KB is a must for us ; and 2) At home, when we have a LOT of data to enter, e.g. in our recipe program (Paprika), the KB is always used. NOW, in both situations, the iPad is propped on a stand on a table w/ the KB in front - I've occasionally 'juggled' the two on my lap, but a frustrating experience. Just my 2 cents for your consideration.