Cream of the Crop
It really doesn't get any better than this. I purchased the Heritage SVT-CL along with the Heritage 810E cabinet and there really are no words to describe it--but I'll try.
First off, the tone is simply amazing. I haven't been able to make this rig sound bad. At low gain, the tubes give a jazz bass a nice warm, thick, but clear tone. It's that perfect mix of body and clarity. You can easily hear the subtle nuances of a lick played in the upper registers and when the player drops to the bottom frets on the low strings, it just hits hard. You can hear an unquestionable difference between when you dig into the strings or just lightly pluck one. Inexpensive basses sound instantly better; quality basses just sound insane.
At high gain, you get that perfect grunge sound (think Muse), nicely broken up by the tubes going to work. At the same time, you still get the clarity of the bass's tone. It's really simply something that must be heard in person.
Aside from that, at 300 watts, this puppy gets LOUD. I personally fear ever trying to use it in my house as I am certain that even with the volume at 9:00, it will bust the seals on any nearby windows. I am not exaggerating or joking. I'm dead serious that I will not use it paired with the 810E in my house. It's just not worth it. This must be carefully used in a venue that can handle it if you're going to pair it with a full-stack cab and it's probably not a good idea to use it if placed against a wall (unless it's concrete or something), but that would be a tone killer anyway. Just a warning. I've paired it with a Mesa 4x10 (not sure of the exact model) and it was much tamer on the volume side.
In recordings, the tone from this amp and it's mated cabinet is perfect. Even with no EQ or compression, sound from it sat well in mixes (of course some tweaking ultimately occurs in any mix... but it was simply uncanny how well it sounded out of the box with no effort).
The bottom line: if you have the money for it and you are serious about your bass tone, this head is a winner. If you don't have the money, save your money and wait to buy it when you can afford it rather than buying something below it. This is a quality piece of gear that will last a lifetime if well cared for. It's built like a tank and will serve as a true workhorse for any serious bassist. Plus, there's nothing like showing up to a gig with legit gear (and knowing how to use it). You'll always be taken seriously with such a rig in tow. :)