My thoughts are to switch to DCC as soon as possible.  With the advent of sound and all the other great things DCC can do, you should take advantage of it. 

I just got my first DCC sound equipt steamer (installed lok sound into 2-8-0 consolidated) and it bumped the fun and interest factor 10 fold.  I love it!!!!

building steam, ring the bells, toot the horn grind it into gear and start off slow, chuff chuff chuff and build up speed....wo hoo!  blasting the horn as you enter and exit tunnels, the realism is fantastic!  I tell ya it turned this 46 year old into a kid again. 

Again thanks to all for the help.  I went with the 2-8-0 and am having sound and DCC installed.  I cannot wait to run it.  I have a dcc diesel but my scene cried for steam and having sound is going to be great fun. 
Thanks again, i will keep you updated.
David

Thanks for the replies so far.  Glenn, I appreciate your input, I only wish I could modify it but I have laid the scenery etc....  This was my first project and I am learning a lot.  Next time I will go for less grade and larger radius.  Cant tell my wife I am starting another project quite yet....

Hello,

I have built the Scenic Ridge layout and want to use a Steam Locomotive.  I would like to add DCC and sound.  I have looked at the 4-8-2 Light Mountain but heard they are iffy on the tight radius.  I heard the heavy mountain might work better, is this true?  I suppose my next choice would be the 2-8-0.  Any input or suggestions that would help better define my choice?  Again the radius is my key concern, 4% grade would be next issue. 

Thanks!

David