Avoiding BDC in development.

Hello all,

I have very many custom developments in 4.0B ver with IS Oil add-on which posts transactions via BDCs.

We are upgrading to Enterprise version and I would like to know :

(a) How to find out if BDCs can be replaced by function call, Bapis, etc. For e.g I want to know whether I can avoid BDCs for o4F1/o4G1/o4H1 - Shipment/LC/DC. I have searched OSS but no luck.

(b) BDCs give error each time some customising changes, hence I would like to avoid it.

Is there a better way of doing without BDCs ? Where to find the answers ?