What do you loose if you use the standard mail template and IMAP

I was demoing Lotus Notes to a potential client and they were really interested.

They do have some enthusiastic IMAP users so IMAP is a requirement. We tried IMAP with the standard Notes mail template and it seemed to work OK. They need the layered calendar view in the 85 template so the IMAP templates ( from R5 ) is not an option.

What issues we will get if we use the IMAP with the standard 85 template ?

They want to choose Lotus over Group wise and Microsoft because

>They really like it for its cross platform support ( MAC, Linux and Windows ),
> Because it looks similar on each client
> Because of Traveler with Nokia
> Cost

Thanks, Sean