Someone wants to invest in my company has given my these options. What option is best and why?

Option 1: $100,000 common units

• purchase common units at$4
• one board seat
• right of first refusal on up to $400K of any future equity raise

Option 2: $500,000 convertible notes

• One year notes bearing simple interest at 8% per annum
• principal and interest converts into equity issued in the next equity raise at a price per share equal to 75% of the price paid by other investors
• restriction at additional debt
• warrants to purchase 10,000 units at $.01 per unit

I think the first option is first but can you explain which one it is best and why