Steve I flew helicopters for 7 years before crossing over to the Hawker business jet, (FlightSafety Level D sim and the works) And withing about 3 months flying high performance airplanes was really easy.
To me the big difference is that in Airplanes you don't really fly them, you operate them, your decision making skills will rust because everything is pretty much laid out for your, your route, your weight, the company dispachers, SOP's, and stadarization will keep you safe, and if you do your foolproof checklists from 1 thru 100,000 you are pretty much set to go.
Landings will be a piece of cake as you as as a helicopter pilot can tell perfectly if you are 20 feet high or 6 inches high, you previous job was all about hand flying skills with eye to hand coordination, you will be able to tell from looking outside if you are going 120 kts and 50 feet without having to listen to the copilot call Vref, 50 feet, and your VFR patterns will be fun.
I have been recently going jumpseat in the A320 as my new boss own more than 10 of them, and I was amazed at how the pilots did practically nothing from 120 miles out, it was hilarious, when flaring the airplane started saying "retard, retard, retard, and I thought the pilot had done something wrong, but it was ordering him to pull the power back!! What has this world come to when the aircraft tell the pilot what to do?!
The other way around is not the same, I fly part time for the Mexico City police and I have copilot who has 9000 hours of heavy jet time, he's 36 years old and has a dream of becoming a helicopter pilot, during his landings I could hear his heartbeat and needless to say the AS350B3's shock absorbers compress
I don't think he can even hold the nose straight during a pick up to hover and he's been flying helicopters on and off for 3 years.
Have fun!!!!
BTW: I felt so useless and tied up in the cockpit of a Jet that I had to come back to helicopters.