A choice between IB and CM

you're talking about sales and trading vs ibanking? there are at least a dozen threads on this already, read through them.

In my case CM is not about trasing and sales. It's more likely to imply some research or structuring related work

structuring often sits with trading though.

Somewhere at this forum I've found out an opinion that traders are likely to neglect the advices from research analysts. I've looked through many threads about trading and IB here, but they tend to dedicated to the comparison of hours, pay and exit opps. What is important for me, whether these long hours in M&A or ECM are filled mostly by a challenging analytic work or a grind. It would be great to know how it actually works.

Is it write that traders and sales play the major role in CM while other groups just provide a support for them?

'Is it write that traders and sales play the major role in CM while other groups just provide a support for them? '

yes this is generally correct. they are the profit centers.

'What is important for me, whether these long hours in M&A or ECM are filled mostly by a challenging analytic work or a grind. It would be great to know how it actually works.'

all these jobs have elements of both. read some of the older threads first.

Thanks for advice, this time I've really managed to learn smth new about the industry. To state my problem clearly, I have to choose between interships in ML IB(it has DCM/ECM, M&A, LevFin among the subdivisions, though I can be sure only that I won't be rotated through sales or other relationship work) and Lehman CM. Both pursuits are in London

Still cannot decide

Choose ML IBK. You will always be able to switch to capital markets after M&A. To make a vice verca switch might be harder.

Thanks for the hint. I've read dozens of messages saying that M&A is by far better than for example ECM\DCM. Is it really that way?