HubSpot CRM does the basics really well and the tiered pricing model allows you to try things out as your business grows. All of the support documentation and training is excellent (if a bit annoying and American... but you can avoid the videos if you want).
Some advanced features you might find in a tool such as Salesforce or Marketo are not present.
Start with the freemium stuff, the free version of the CRM, the free sales tools and the free Marketing package, you'll soon find out if it's going to be useful for your business or not.
HubSpot CRM allows us to connect our prospect and customer list to the the thing that really matters, our marketing activity. It's great for the sales team to keep up to date with their conversations but it's the automation and data analysis side that really makes it a useful tool. Your prospects lists becomes your marketing strategy.