There's an interesting post on stackoverflow concerning the quality of the Eclipse WTP which seems to be decreasing with every major release:
Our company is using eclipse since several years now (we are using WTP since release 0.7)
I am currently evaluating eclipse 3.6.2 with WTP 3.2.3 (...)
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WTP 3.2.3 seems to be much slower than 3.0.4.
In fact I am really wondering why WTP gets slower with each release.
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We only need basic WTP functionality for developing jsps, xmls and xsd. We don't need high sophistic features like Dali (should JPA tools really covered by a webtools project?), Libra or a visual xml editor in the first place.
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The worst thing is that I've got the feeling that the WTP dev team does not care much about performance (e.g. have a look at the http://wiki.eclipse.org/WTP_Performance_Tests page - last update took place in 2008).
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But obviously the project has a problem with its quality assurance, especially in terms of performance which affects usability and user acceptance.
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[The] team should focus on the things which are essential to most of the users in the first place and afterwards work on implementing super-duper-features.
Does this sound familar to you? I had a déjà-vu while reading this post.
You can find the whole stackoverflow post here:
http://stackoverflow.com/questions/5433991/eclipse-webtools-project-wtp-and-its-performance-quality