I'm replying to an old(ish) thread just to add my experience to the forum for anybody looking for the same information. Our "35-employee but growing" company evaluated many open source ERP projects and narrowed the choice down to Open ERP or ADempiere. The strengths of each in my opinion (as a user client) are:
- Slightly better out-of-the-box functionality in many areas (small things like: automatically assigning costs, e.j. shipping costs, according to preset rules to give more valid true product cost information; allowing closing of periods on a per journal basis; sophisticated multi-company accounting system). The design seems more streamlined and geared towards real business use, whereas in Open ERP you have to configure everything to work the way you want.
- More stable (not a single error in limited testing). Uses "industrial strength" Java platform.
- More difficult to get started with (both from an install and a user perspective).
- Probably more expensive to implement if you hire an outside implementor (we were quoted around $50,000 usd)
- Is owned by the community (which is good and bad)
- Much easier to extend due to modular approach and "easy" Python code.
- Easy to install.
- Bigger, more active, community doing smaller implementations. Probably easier to find alternative companies for support.
- Once you learn to avoid the bugs, it's pretty stable
Version 6 seems better than version 5 so far.
- Lots of nice features that make the system easy to use, like duplicating records and bringing up data.
- Is owned by an editor with investment and a business model. Probably has a better chance of being developed further more quickly.
In the end we've decided to go for Open ERP v6 mainly because we believe it will be easier (cheaper) to adapt to our needs in the future (including interfacing with other systems) and to support.
What would be great is if Open ERP's functionality could be brought up to the same standard as ADempiere/Compiere. That would tip the scales very highly in Open ERPs favor.