That's just plain bad advice. There's a lot of amps out there for many different purposes. People always say "you gotta get a toob amp! TOOOOOBBBS!!!!!!", when in reality, tube amps are for specific purposes.
Tube amps don't really shine unless you're playing LOUD...so they're great for playing live or if you need something to overpower your drummer's new double kick bass kit. They also take a good 15-30 minutes to warm up properly, and you have to go in an replace tubes once in a while. Yeah, they do have a warm sound (kind of like how an LP sounds warm compared to a CD), but they would be a poor choice if you're going to be practicing in a bedroom.
Solid state amps don't have a warm up period, are pretty much trouble free, and you don't have to crank them up for them to preform. They'll also have effect doo-dads and gizmos to make things more convienient, and aren't quite as huge as say...a Marshall half stack (not to mention a lot cheaper). If you're practicing...hell...if you're playing live even...solid state amps are great! It's all a matter of picking a sound you like.
To make my point, I have an early 80's Traynor Bloc 50 that I use as my main workhorse and people I gig with would mame someone to get it. No tubes on it- just a well constructed (although rare) solid state amp.