1) you will not get Promotion, No Increment even you will never get your full variable ever.
2) HCL will make you fool at the time of asking Salary Package because lots of components are included in this,
PF, TDS, Gratuity, Variable, Life Insurance that will be deducted from your CTC in-hand salary will be less as you think.
3) Not only this once you came on bench immediately they ask you to relocate to other location infect they force to relocate.
4) if you get the offer from other company then they will not give you release if you are on project if they are giving you release bit early then you have to take approval from higher management and they same days which you have asked early release hcl will deduct the benefits,
5) if you are on bench and reigned from hcl and you do not want to go early then HR Person will force you to go early they will create lots of pressure on you. but do not worry until unless you did not confirm to early release they can not release you before 3-Months.
6) lots of politics from Chennai Management, Mostly cream project keep at Chennai location and mostly Management will be form Chennai location.