You can invest in the SBI Small & Midcap fund if it suits your risk appetite. Remember that this category is for aggressive investors with a high appetite for risk.
The funds tend to perform well over long periods of time. It has done well over the last five years but thats not a guarantee for future performance.
When you invest, ensure you only do in Direct Plan of this Funds. You then get upto 40% more in long term portfolio size by avoiding commissions and brokers.
If already invested, then switching to direct is really easy. Click here to start your switch.