European Banks in Hong Kong

Depends on the product.

Ignoring Chinese and American banks that traditionally dominate this area, HSBC is really strong in Bonds (both HY and IG; HKD and Offshore CNY); UBS does well, (historically CS did too but not sure where they are now) and I'd argue are stronger than DB, Soc Gen, Credit Agricole, and BNP (but differences can be marginal). This is just generic, and sector teams are obviously different. Stan Chart, BNP and Soc Gen historically do well in infrastructure (mostly energy) and lending to capital intensive businesses in Asia; if you look at the top deals (excluding tech), they are typically in materials, financials and energy & power. 

On ECM, the market is (again) dominated by Chinese banks, followed by American banks. Outside of those, UBS and HSBC are stronger than the rest of European banks, who have varying degree of strengths depending on the sector they are stronger in (similar to DCM). Another thing to consider is which (if any) European banks tend to be lead underwriters (deals on which you get meaningful experience). HSBC is a likely standout out in that regard, and is a top rated MLA & Equity offerings shop. UBS and Stan Chart also do well, with UBS being great at equity offerings & IPO (IPO has historically been dominated by Chinese Banks, GS + MS). 

On M&A, DB is pretty strong along with CS, UBS, and Barclays. Lot of M&A tables are skewed because advisers get credit for simply providing a balance sheet (you can argue that's the case everywhere, but particularly more so in Asia). M&A is never likely to be a lead product offering for any bank, and most work is tied to either DCM or ECM. CS's M&A business has slowed down because their past approach of using their balance sheet/Wealth Management business to aggressively drive M&A business is now changing, given their global struggle and scandals. Not sure how DB's struggles mean for their overall IB strategy (seems like they remain committed). Somehow UBS has done a tremendous job in keeping a pretty strong profile in Asia, despite challenges in growing their own global IB business). Someone once told me this is because UBS has historically had more flexibility in offering greater comp at rainmaker level to its IB MDs in Asia compared to other European banks (somewhat credited to Orcel's legacy). CS had built a great IB franchise to tag along with their ECM/DCM business which is tied to WM; expect more exodus at CS as the bank revamps its overall strategy to be in line with WM and less balance sheet & IB focused. 

In terms of pay, I think this is broadly dependent on how aggressive the respective banks are re. their pay generally (and not just in Asia). You can probably read about them in compensation reports online. French Banks have traditionally always been more conservative with pay and will expectedly pay a notch below DB, CS and UBS. CS may try to reign in bonuses going forward. Not sure about HSBC, but I'd think its in line with Barclays. Many years ago, the foreign banks started to do away with "expat comp" benefits, that had previously artificially inflated the overall comp figures, so you should be looking at recent comp figures for a more accurate assessment. 

I'm not an Asian expert, but I've close connections in HK/SG who work/recently worked in the industry there. Generally, ECM & DCM fees will be about ~40% each of the pool, and rest of it is M&A. If you want good experience, you should always target a good ECM/DCM shop before a stronger M&A shop.  Most clients care about brand (American banks > European Banks, all other things being equal) and also how your experience fares in helping companies position their equity growth story to investors (which you will pick up in a traditional IPO/Cap raise process).

In terms of directly answering the question whether they are worth joining: that's really dependent on what your objectives are. Assuming you have local interest in working in greater China markets (and associated skills such as language fluency), most of these banks are fairly reputable and good places to work, and will open doors for you as you gain good experience. Personally heard that ECM/cap raising experience is really valuable as that's what drives a lot of the "high profiled" IB business in Asia. Also, the recent rise (but not so recent as they have been at it for a number of years now) of Chinese banks (that pretty much dominate the tables across ECM/DCM) is something to reckon with, and wonder how much of the business they have eaten away from the European banks.