I use the GT-10B, not sure if that sounds as a "pedal". I've previously owned a DD-3, an OC-3, and an ODB-3. A lot of people hate on the ODB-3 but I liked it, and use a model of it in my multi-FX unit now. As people say so often, it sounds bad UNLESS you spend some time tweaking it, as it has a massive gain range and is very sensitive; what you run into it has a big impact on how it sounds, and how it responds dynamically.
The OC-3 is good, tracks well but barely any better than the OC-2, which is disappointing considering how much newer it is. The Polyphonic mode is handy, even on bass, but makes the effect sound worse than the classic "OC-2" mode. The distortion in it is actually very usable, and works well with the octaver. The bass input jack is a little bit redundant cause as far as I could tell, all it does is change the tone of the distortion. As mentioned previously, I think the Boss bass inputs generally don't do much except water the effect down a little. Worth it for extra tonal range though.
The DD-3 was great. It's a pretty standard delay really, but hey, it's 20 years old so what do you expect. It has a good enough delay time range, though the longer times on the DD-6 and DD-7 are very welcome additions. It's also lacking the extra features of those pedals, but for a basic, solid digital delay pedal, I think it's the best there is. I would recommend the newer versions over it because they don't cost much more now, and those extra features will come in handy.
I've been using the GT-10B for over four years and it's a tank. I have it set up in manual mode, in which it effectively emulates having three effects stompboxes (with tap tempo for the delay), a tuner, and an expression pedal that switches between a volume pedal and an effect. Another switch controls the expression pedal, switching between bass wah and a whammy effect. I have different banks for different whammy effects (switchable with dedicated up/down switches), but so far I'm only using two. I have plans for a third though.