Your speed would depend on a number of factors.
A different router/modem might improve the situation, as would the profile that your ISP as provided.
The line and exchange equipment would also have to be taken into consideration. Run a number of different speed, MTU and Trace tests, then compare the results, and ask your ISP what speed you should expect. If your tests give a far lower result that what the ISP is suggesting, then get them involved.
If you haven't done it before, just reset (switch off, leave for a while, then switch back on) your present router, and see if that makes a difference.
Another point worth considering, is the browser that you are using, and whether that as been updated. Even your computer might give a slow speed, if there are any maintenance problems.
But going back to your original question. There a a number of websites that you can check for reviews on router/modems, so it might be worth while to start there. One particular site worth a visit http://www.kitz.co.uk/