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

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