Pavan, I would suggest you to give a try to it. Its a win-win situation for you as you will have free access to SEMrush pro version worth $47 for 14 days and you are not going to lose anything. If you like it, continue using it. With the kind of features SEMrush is offering, there is no alternative as such. With SEMrush, you can track 500 keywords with Pro version (price $99.95) and with Moz, you have to pay $99 for tracking 300 keywords only. So feature wise, SEMrush is much better than Moz or any other SEO/SEM tool available in the market.
Now keep in mind that, based on their stated crawling guidelines, the stronger links from stronger sites tend to get crawled more frequently so the spammiest of the spammy link approaches might not get picked up on. For that level of deep research a historical report from Majestic SEO and a link status checker, like Advanced Link Manager, is likely a better bet.
Quick tip: While doing keyword research with SEMrush, do not select the keywords with search volume more than 1000 per month, as they require a lot of efforts to get required traffic for your site. Choose the keywords between 500 to 1000 per month search volume (or even below) so you can get top 3 or at least first page rankings even if you’ve a new website.
Semrush has helped our organization in different ways as it not just improved our website ranking but also enable us to make our clients happy by providing the best results. Semrush helped us by letting us know about the backlink opportunities. The tool also allows generating performance report which saved our time as we were able to send SEO performance reports to our clients any time.
Lite allows you to have a 7 day trial for $7. After the trial ends, it costs $99 per month or $990 per year. This plan allows you to track up to 5 projects (websites) and track 500 keywords per project. You can search 25 batches of keywords per day, but you can search up to 10,000 keywords per batch. I like to use it to search multiple ideas for long tail keywords at once so I don't use up all my searches.