I got my ME-90B as soon as they were released last year as I wanted to dramatically shrink my rig and clean up my sound. Having used it for a few different gigs and rehearsals over the last 6 months, I thought I'd share me experience.
First up, the context:
* The type of music I'm playing is all covers of 80-00's pop/rock in a band with both male and female vocals, 2 guitars, drums. Keys all come from backing tracks that I make. With that in mind, I don't need too many different sounds.
* I play a 5-string Yamaha TRBX305 bass with active pickups
* The rig I wanted to replace was my Trace Elliot AH350SM with GP7 preamp (yes, the green writing and UV light tube) that weighs a tonne and a Peavey 15" BW speaker box (also weighs a tonne), both of which I've had since the early 90's and love the sound of, but do not love lugging around. FX-wise I was using a BOSS OC2 (or OC5) Octaver pedal, BOSS CE-2B Chorus pedal, Ibanez TS10 Tube Screamer pedal, BOSS TU-3 tuner pedal, and Alesis 3630 rack compressor. About 1-2 years ago I had replaced the BOSS CE-2B with the BOSS GT-1B. I had wanted to also retire the Tube Screamer and BOSS Octaver pedals but the GT-1B just didn't deliver on that front. The GT-1B was also a problem for me because I found the pedal buttons just too small, and too close together. I only have a size 11 shoe, but I found I had to be super careful to not hit 2 pedal buttons at the same time.
* My goal was to replace all the above amps and effects with the ME-90B so I could go ampless on stage (guitarists in my band were doing same), and use the balanced DI from the ME-90B to go directly into our band's Behringer X32 that we use for our IEM rig with a split for FoH.
Overall, I've been reasonably happy with the result and have achieved the goal of dramatically downsizing my rig.
Pros:
* ME-90B build construction is really sturdy, and balanced DI sound is nice and clean.
* Most of the sounds have met my need, and in particular, the compressors are good. My fave is the MXR, One of our regular PA Ops is a bass player and we nerd out over gear talk prior to gigs. It also means I have another bass player for feedback on how things are sounding out front. He was so happy with the sound I was giving him that he wasn't touching it at all.
Cons:
* I still prefer my BOSS OC2 (or even OC5) over the octaver in the ME-90B. The sort of sounds I'm looking to replicate range from Noiseworks to Peter Gabriel.
* I don't really like the overdrives/distortions. I find them all a bit 'fizzy'. I'm still trying to avoid bringing my Tube Screamer out of retirement for nice warm subtle drive by using a combination of in-box overdrive, preamp, and cab IR (see below).
* The various preamps are OK, but I found the sounds really came to life once I started using the 3rd party cab IRs. They've been recommended in this thread earlier, and I'm also recommending them as a starting point, go get the Shift Line Bass IR pack -
Shift Line Bass IR Pack. It's a bit like the difference between a passive bass going through a DI box with flat EQ versus an active bass, split DI and with a mic'd cabinet, EQ's and with a nice warm compressor.
The compromises I accept due to the price:
* I wish the display panel was more than a 2 digit display for bank and patch number. I'd love to see patch naming be visible. I struggle to remember whether "14" or "21" is my fretless patch.
* I wish there was some sort of input level indicator. There are times where I fell like I'm hearing clipping due to my input level being too hot, and back my bass volume back a bit. This is not ideal as it makes it hard to maintain consistent gain staging,
* I wish it had MIDI In for MIDI automation from other MIDI devices or hardware MIDI playback devices (e.g. using a B.Beat Live for live backing tracks AND MIDI program changes)
* I wish you could load more than 3 IRs.