Bitrix24

Overall, working with Bitrix24 as my main project management software has really improving my team effectiveness in developing a product and increase our time spend on organizing project that has short due-date.

Well, I used Bitrix a lot of time and you know, the things doesn`t change a lot of time. For sure, Bitrix is got a lot of features and integrations. But the question of quality of these features are opened. For 100% benefits of features, you should to charge the money for add-ons, or you should to do some of dev-jobs. This is not cool for the small teams.
Overall: for employees and some teams from CIS this software is 'must-have'. If you want to change something, you can do it, because a lot of software are available. And a lot of these are good enough for any-sized teams.

It has been 2 years and as of now, i have not thought to look for any other platform. if ever anything pops up, i consult my service provider, and every time we see that it can be done or added to my existing package.

i will give it 5 starts for making my life easier.

I'm a partner, their sales team is in UTC+2 9:00 AM to 6:00 PM. Support is UTC 8 - 5:30, tech support is UTC+3 8:30 to 5. You have to be awake between Midnight and 4 to get support from them or even a simple response. If a thing doesnt work for their customers they have to goto their partners. and subscribe a paid plan for them to fix it. OTP was working and suddenly stopped working. and Only my account was setup with OTP and not my clients. Client wants to do monthly plan and bitrix wants me to sign them for quarterly plan. Poor ethics. Partners cant sell you one month, they have to sell only 3 months minimum. I lost a client because of my client wanted one month and bitrix wants me to sign them up for three months. there are way better CRMs which will support you in US time zone. Bitrix sales and tech support uses google translator for responding. so if they dont understand what you are saying them, its googles fault. Its lot of hassles, and if you have great customer service you can manage any software. try few other crms and read a lot of reviews before going for bitrix else you will be stuck like my customer after an year half way down deep.