Depends on your cabinte and speakers you have and what type of music you play. I have a a JTM45 I BUILT FROM METRO AND LOVE IT. That being said, I hate it with my VM 425A cab. I use a 1960AV and it is great. I use the 425 with my JCM800 2204 and it is great. I found the JTM to have less useable tones from the music made in the 80's and up . It is great for the older stuff and blues.
Good luck, I think you should hang on to the VM and save for the Metro. I have had a few tube amps in the last couple years and found my faves so far.
1. JCM800 2204
2. Metro JTM45
3. Sovtek Mig 50
4. Class 5
recently sold- DSL100- sterile sounding, Vintage modern lots of service and breaking down issues, Mesa Triple Rec- couldnt find a sound I loved and the ones I liked my Marshall could do.
Sometimes you have to go through a few to find what you are looking for. If you love the VM keep it If not keep looking into something else
My wish list amp is a Metro '68 spec they sound awesome.
Best wishes, TBW