It all depends on your knowledge of SQL and/or VBA. If you are developing apps with VBA and SQL in Access, it will be an easy and rewarding experience. Things I did in VBA either filtered into Transact SQL or DTS.
If you are simply using the wizards wihtout any code, you will find setting up databases easy, but the real glory of Transact SQL will be much tougher.
The early bird gets the worm, but the second mouse gets the cheese.